Agitator for stoker hoppers



1,444,888. 0. C. SHELDON. AGITATOR FOR STOKER HOPPERS.

FILED MAR. 1, I920- 2 SHEETS-SHEET I Feb. 13, 1923.

O. C. SHELDON. AGITATOR FOR srom HOPPE 2 SHEETS-SHEET 2.

FILED MAR. 1, I920- Patented Pele. id, 19230 teases r errata one o. SHELDON, or wononsrrnn, i'rnssnonnsnrrs, essrenon 'ro sanro'nn niiinir s'roKEn co, or wononsrnn, rmssnonusnrrrs, A .ooiaronerron or ransseorru- AGITATOB- FOR STOKEl-t K01 91 118RS.

Application area March 1, 1920. Seria1N0w3.62,611.

citizen of the United States, residing at Wor cester,.in the county'of Worcesterand State of Massachusetts, have inventedanew andusefulAgitat-or for Stoker Hoppers, of .whichthe following is a specification.

This invention relates to a device ;for breaking up and preventing the formation of arches in a body of coarse materialasiit is fed down through a hopper.

a The principal objects of the invention are to provide an improved device for thispurpose which can be connected easily with the feeding mechanism so as to be operated thereby and which will beefiicient for-the purpose of Iproducingt-he tendency of the arches that may beformed; also to provide a construction in which the agitationwill occur atithe top of the hopperiaswelllatat the bottom, the movement always beingin opposite directions the top andhottoni, thus assisting in keeping the material in loose condition especially when applied to a plunger feeding stoker provided with an extension at thetop of the hopper. The invention also involves improvements in the shape-and construction of the agitator itself its relationto the-hopper, and the means by which the agitator. is driven.

Reference-is to he'had to the accompanying drawing in which v F 1 is an end View of a hopper for feeding a stoker, showing a preferred embodiab vp single p e e ofmet n .of a gen- ,era'hshape similar tothecross section of the hopper. At any-rate it is provided with a lower bar 27 which lies over one ofthe partitions 26 Whendn neutral position and is parment of the invention appliedthereto and parts broken away to showits. construction; Fig. .2 is a'sectional view of the same through the center of one ofthe plunger throats;

Fig; 3 is a sectional view on the line 3+3 ,Of Fig. 2; s

Fig. 4c is a plan of the operating mechanism taken at the point indicated by the arrow 4 in Fig. 1;

,Fig. 5 is anedge ,view as indicated by'the arrow 5 in Fig. 1; and v Fig. 6 is an end view looking in the direction of the arrow Gin Fig. 5.

Several devices have been invented for keeping the arches broken upin'a body of coal fed down a substantially trapezoidal shaped hopper-to aseries of feeding plungers. Simple as this problem seems it has been difficult; to find a thoroughly practical and; efiicient device [for the purpose. 1 Althoughgthisginvention is capable of use =1Il connection gvvith otl'ie-r types ofimecha-nism v for feeding coal {and other coarse I material I have shown-inns applied to a hopper 10 01 .21

' welhknowntype whichfeedsy-coal down} into a series of transverse throats 11; .at'the :bottom of whichvare plungers 12 that force the ocal directly int .the stoker -13.'

These plungers, asi ha's been the case'heretofore, are operated frc n agate llvh'av'ing cranksor eccentrics for operating connectingrods '15 c which are connected {b0 the several plungers togme them ,analternat ng motion.

Inthe present instance I have shown the I shaft l l as provided with a disc 16 on the fuel to form arches and breaking up any end supporting a second 1 disc 17 havinggan eccentric pinlfl. Thisgpin-is connected with a :link20 which it -recipro cates ZiSxthe :shaft .1 1 rotates. This link transmitsmotionsby ,a bell-crankQl to an openating rod 22 which extends longitudinally of the hopper for; opcrating the agitators as-willappear'. This rod-isshown as provided withpairs ofpins 23 spaced apart for recelvlng the-gendsof the .several agitators 241' between them,

enough play being allowed to ipfermitzo'f a The number-pf these agitators preferably is equal to the number of. partitions 26-hetween the several throats 1,1 in which the plunger-s 12 are located. 3

Each of the agitators 245 is made preferallel with the pivot shaft- 25 above which supports the agitator in the-Walls of thehopper. The agitator is also provided with a the top ,ofthehopper. This is particularly desirable when thehopper is provided with an extension as 29 because then it is more likely to 'besuostantially full of coal.

shafts 25, and which may conveniently be made parallelwith the front and rear walls ,frce motion for swinging thesB 'l gagitators-Qionthew pivots 25ers w ll be obvious.

of the hopper 10 to provide for movement along these walls so as to break up the ends of any arches that form in a direction parallel to the movement of the plungers. Such arches are broken up by the movement of this agitator simultaneously with the rock ing of the agitator into a position to break up an arch formed in a direction transverse thereto, the two types of arches being indicated' in Figs. 2 and 3 respectively.

One of the features of these oscillating frames that is important,'is that they give motion in opposite directions in the upper and lower portions of the hopper. Ubviously, while the lower parts of the frames below their trunnions are being moved in one direction, the parts of the frames above their trunnions are being moved in an opposite direction and this is a marked advantage in agitating the coal in the hopper. This movement in opposite direction tends to mix up the coal and prevents any possibility ofit riding as a mass back and forth on the agitator.

From what has been said it will be seen that a simple device is provided for this purpose and one which will tend to agitate the coal throughout a relatively great area i and not merely to break up the arches after the hopper.

they have formed and become wedged into the bottom or more contracted part of the hopper. This is an important feature because it tends to prevent the formation of the arches originally and thus does not necessitate the application of the same amount of power that would be required to dislodge arches that had already formed, composed of lumps crowded and wedged together. This has proved efficient in practice and it will be seen that there is no way in which it is likely to bind, and there are no parts on which an alternate backward and forward bending strain is exerted of a sufficiently high degree to cause crystallization of the metal.

Although I have illustrated and described only a single form of the invention I am aware of the fact that modifications can be made therein and that the invention can be applied to other types of hoppers for feeding coarse material without departing from the scope of the invention as can pressedin the claims.

Therefore I do not wish to be limited to all the details of construction herein shown and described, but what I do claim is:-

1. In a device for feeding coarse material, the combination with a hopper and means for feeding the material from the bottom thereof, of means in the upper and lower parts of the hopper for simultaneously creating a movement of the material in opposite directions in the upper and lower parts of 2. The combination of a hopper for repivotally mounted over the nee-mass ceiving fuel and feeding it downwardly, and a plunger for positively feeding the fuel at the bottom of the hopper, with a device movable at the bottom of the hopper in a horizontal longitudinal direction transversely to the direction of motion of the plunger, and means movable thereby in the opposite direction for agitating the coal in the top of the hopper. v

3. In a device for feeding coarse material, the combination with a hopper, of a frame pivotally mounted in saidhopper and having a cross bar at the toplocated below the top of the hopper for agitating the material in the hopper, and means for oscillating said frame.

4. In a device for feeding coarse material, the combination with a hopper having a slanting wall for feeding the material downwardly, of a frame pivotally mounted in said hopper and having a cross bar at the bottom and one at the top both located below the top of the hopper, and means extending along the hopper for oscillating said frame on an intermediate axis substantially parallel with said bars.

5. The combination with a hopper having an extension at the top with an agitator therein comprising a transverse shaft, and

a frame pivoted on said shaft and having a barnear the top of the hopper below said extension and extending from the front to the rear of the hopper, and means for swinging said frame on said shaft.

6. In a device for feeding coal, the .combination of a hopper with means at the bottom thereof for discharging the coal therefrom, of aframe located in the hopper, said frame having four sides, two of said sides extending up along the front and rear walls of the hopper and substantially parallel thereto, and the upper and lower sides connecting them within the hopper, and means extending along the hopper'for oscillating said frame on an axis between the top and bottom.

7. In a coal feeding device, the combination of a hopper of substantially trapezoidal form in cross section, a series of throats at the bottom extending transversely with respect to the hopper and receiving the coal therefrom, and means at the bottoms of said. throats for positively discharging coal therefrom, with a series of agitators partitions between said throats.

S. In a coal feeding device, the combination of a hopper of substantially trapezoidal form in cross section, a series of throats at the bottom extending trans-- agitators pivotally mounted over the paring transverse throats provided with transa discharging material therefrom, a plurality 10 of swinging transverse frames in the hopper over said partitions, and means whereby the frames are swung at the bottom outwardly and upwardly fromsaid partitions into the body of material between the partitions.

In testimony whereof 1 have hereunto affixed my signature.

is o. SHELDON, 

